/**
 * 
 * Copyright (C) 2011 Cody Stoutenburg . All rights reserved.
 *
 *       This program is free software; you can redistribute it and/or
 *       modify it under the terms of the GNU Lesser General Public License
 *       as published by the Free Software Foundation; either version 2.1
 *       of the License, or (at your option) any later version.
 *
 *       This program is distributed in the hope that it will be useful,
 *       but WITHOUT ANY WARRANTY; without even the implied warranty of
 *       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *       GNU Lesser General Public License for more details.
 *
 *       You should have received a copy of the GNU Lesser General Public License
 *       along with this program; if not, write to the Free Software
 *       Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA. 
 * 
 */
package ca.usherbrooke.behaviours;

import jade.core.Agent;
import jade.lang.acl.ACLMessage;
import jade.lang.acl.MessageTemplate;

/**
 * @author Cody Stoutenburg
 * 
 */
public abstract class BasicSubscriberBehaviour<E extends Agent> extends
		BasicCyclicBehaviour<E> {

	private static final long serialVersionUID = 1L;

	private static MessageTemplate SUBSCRIPTION_TEMPLATE = MessageTemplate.and(
			MessageTemplate
					.MatchProtocol(BasicSubscriptionBehaviour.MY_SUBSCRIBE),
			MessageTemplate.MatchPerformative(ACLMessage.INFORM));

	private final MessageTemplate receive;

	public BasicSubscriberBehaviour(E agent, ACLMessage msg,
			MessageTemplate receive) {
		super(agent);
		msg.setProtocol(BasicSubscriptionBehaviour.MY_SUBSCRIBE);
		msg.setPerformative(ACLMessage.SUBSCRIBE);
		this.getAgent().send(msg);

		this.receive = receive;
	}

	public BasicSubscriberBehaviour(E agent, ACLMessage msg) {
		this(agent, msg, SUBSCRIPTION_TEMPLATE);
	}

	@Override
	public void action() {
		ACLMessage msg = this.getAgent().receive(receive);
		ACLMessage previous = null;
		while (msg != null) {
			previous = msg;
			msg = this.getAgent().receive(receive);
		}
		if (previous != null) {
			messageReceived(previous);
		} else {
			block();
		}
	}

	protected abstract void messageReceived(ACLMessage msg);
}
